Democrats who oppose the Trump administration’s move to add a citizenship question to the 2020 U.S. Census held a press conference at the Capitol on Tuesday, including Rep. William Lacy Clay Jr. (D-MO), who compared it to killings based on race.

“Let’s not fool each other,” Clay said. “We know what this is.”

“This is the Trump administration’s American version of ethnic cleansing in order to blur the lines of accuracy in the Census,” Clay said. “That’s what this question is about.”

“That’s what the motivation is,” Clay continued. “This is to have an inaccurate Census so that they can continue denying the fact that this country is becoming more browner and blacker.”

Clay, like many the other Democrats at the press conference, called the citizenship question “unconstitutional.”

House Minority Leader Nancy Pelosi (D-CA) said the addition of the question represented the “desecration of the Constitution.”

Vanita Gupta, who worked in the Obama administration’s Department of Justice’s civil rights division, was also at the press conference.

“A fair and accurate census is really one of the most significant civil rights issues facing the country today,” said Gupta, who now heads the liberal Leadership Conference on Civil and Human Rights.

Gupta called for the decision to be “overturned.”

As Breitbart News reported, those in favor of adding the question, which was last on the Census survey in 1950, have said it is important to know how many citizens and non-citizens are in the United States:

Kansas Secretary of State Kris Kobach told Breitbart News that the move to put the citizenship question back on the Census was a historic victory for Trump’s administration and one that will result in more accurate unemployment data and a better estimate of the illegal alien population.

“This is one of Trump’s most important accomplishments as president,” Kobach said.

“It allows a sovereign nation to know how many citizens it has,” Kobach said. “That’s the craziest part of our Census since 1950. Now we will have an actual count of citizens. That’s one of the most basic things a sovereign nation should be able to do, along with enforcing its borders.”